German Singh, the alleged mastermind behind a plot to kill former Punjab Chief Minister Parkash Singh Badal, was on Friday grilled by the Patiala Police and intelligence officials.
He was brought to CIA staff police station here.
German Singh was on Thursday arrested in Bikaner in a joint operation by the Punjab and Rajasthan Police. German Singh had attacked and looted police rifles in Uttar Pradesh's Shamli district on October 2.
Three men were arrested earlier on Sunday for allegedly looting two rifles and ammunition from a police check post in UP's Shamli district after attacking the policemen and injuring two of them.
The trio - Amrat Singh, Gurjan and Karan Singh - had later revealed that they were linked to militant group Khalistan Liberation Front and were planning to attack former Chief Minister Badal during his political rallies.
On Thursday, the Rajasthan Police arrested pro-Khalistani member Garman Singh from a gurdwara in Bikaner's Kolayat.
Singh is wanted by the ATS of the Punjab and Uttar Pradesh Police.